基于叶绿素荧光技术的紫菜光适应特征研究

通过水样调制式叶绿素荧光仪,对坛紫菜、条斑紫菜叶状体和丝状体在不同光照条件下叶绿素荧光特性进行研究.结果表明:紫菜叶状体和丝状体实际量子效率在光照处理后逐步下降,且随着处理光强的上升,实际量子效率的下降速率更为明显.快速光曲线初始斜率(α)结果与实际量子效率相似,表明光照时间的延长以及光照强度的升高均引起样品实际光能利...

Light adaptation characteristics of porphyra studied by chlorophyll fluorescence technology

The chlorophyll fluorescence characteristics of thallus and conchocelis in both species of Porphyra grown under different light intensities were investigated with Water-PAM chlorophyll fluorometer. Results showed that the effective quantum yield of PSII (Yield) of Porphyra decreased after the treatment, and the effective quantum yield of sample decreased obviously with the increasing of light intensity. Results of the initial slop of rapid light curve (α) are similar with the effective quantum yield of sample, which meant both the time after treatment and the increasing of light intensities Would induce the decreasing of actual light energy use efficiency of Porphyra. The minimum saturating irradiance (I_k) calculated from the rapid light curves (RLC) of thallus and conchocelis in Porphyr were less than 150 μmol·m-2·s-1, which indicates Porphyra was one kind of seaweed adapted to low light intensity. High PAR increased the I_k of Porphyra,which supported the idea that Porphyra had light energy regulatory mechanism to adapt to the changes of light intensities. ANOVA results showed that the effective quantum yield of PSII, the initial slope of rapid light curve (α), the maximum relative electron transport rate (r_ETRmax) of conchocelis in both species of Porphyra decreased significantly with the increasing of light intensities(P<0.05), the effective quantum yield of PSII and the initial slope of rapid light curve of thallus also decreased with the increasing of light intensity, but the maximum relative electron transport rate had little change, which meant conchocelis and thallus of Porphyra might have different response mechanisms to the changes of light intensities. The results of induce curve indicated that thallus of both species of Porphyra grown under high light intensity had higher photochemical quenching (qP) and lower non-photochemical quenching (NPQ) than those grown under low light intensity, which suggested that the light tolerance of thallus of Porphyra could be improved by high light intensity acclimation.